Centrifugal fan.



R. WARG.

CENTHIFUGAL FAN. v PPLlcAnoN man APR. 13, 1914 Patented Oct. 12, 1915.

40 v 1 of which the blades form a part.

ROBERT WARG, OF MILWAUKEE, WISCONSIN.

CENTRIFUGAL FAN.

Speccaton of Letters Patent.

rammed oet. ia, rara.

Application filed April 13, 1914. Serial No. 831,531.

To all whom t may concern Be it known that I, ROBERT VVARG, a citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State of lVisconsin, have invented new and useful Improvements in Centrifugal Fans, of which the following is a description, reference being had to the accompanying drawings, which are a part of this specification.

This invention relates to improvements in centrifugal fans and more particularly to fans or pumps in which the fluid to be moved is taken into the fan axially and is discharged circumferentially.

It is one of the objects of the present invention to provide a centrifugal fan of great rigidity and eiiiciency which is of simple construction and is well adapted for the purpose described. f

A further object of the invention is to provide a centrifugal fan having a rotary member constructed of thin elongated blades arranged in substantially drum-like form to provide a comparatively large intake opening and chamber to permit the free unobstructed ingress of air to the blades. p

A further object of the invention is to provide a centrifugal fan in which the drum is formed of two circumferential lines of blades of which the blades'of the inner line are arranged to drawV and deflect the fluid inwardly toward the inner end of the blades in order to equalize the work on all portions of the blade nd form an eflicient construction.

A fui... l object of the invention 'is to provide a centrifugal fan in which the fluid to be moved is carried by the fan blades a shortk distance and is then discharged' centrifugally from the periphery of the drum A further object of the invention is to provide a centrifugal fan in which the drum is formed of two circumferential lines of blades extending at an oblique angle with relation to the axis of rotation of the drum and also in which the blades of the inner circumferential line extend obliquely at angles crossing the angles of the outer cir- .cumferential line.

With the above and other objects in view the invention consists of the improved centrifugal fan and its parts and combinations as set forth in the claims, and all equivalents thereof.

In the accompanying drawing in which sitioned radial blades 17 and 17.

the same reference characters indicate the same parts in all of the views: Figure 1 is a side view of the improved fan, portions being broken away to show interior construction; Fig. 2 is a vertical central section view .on a larger scale, of the rotary member of Y charge opening 10 formed in a trunk extension 11 projecting from the periphery thereof.' rlhis casing is of ordinary construction and is provided with a journal bearing l2 on its side portion opposite to the inlet opening. The bearing is pivoted to the casing to provide for alining the bearing with a shaft 13 which is journaled in the bearing and eX- tends therethrough and into the casing. The rotary fan member 14 mounted on the shaft within the casing is of drum=like` formation to provide a comparatively large inlet chamber 15 which is of a diameter approximately coinciding with the diameter of the intake opening 9 of the casing and is'in alinement therewith.

The'rotary drum-like member comprises a pair of annular head plates 16 and 16 which are spaced apart by the inner and outercircumferential lines of'elongated closelypo- The inner line of blades extend obliquely from' the annular rear plate 17 to the'front plate 17 and in a direction toward the direction vof rotation of the rotary member, so that, inV drawing in the fluid, the fluid will be engaged and deflected toward the rear annular plate 17 of the said member in its passage between the blades. The outer circumferential line of blades is similar to the inner line except that they extend obliquely inthe opposite direction orin a direction receding from the direction of rrotation of the drum.

This oblique arrangement of the outer bla des serves to Vdeiiect the engaged iiuid toward the front plate of the drum thus providing a construction in which all portions of the blades do their proportionate share of the Work with the result that a large volume of gether. l

The rotary drum is connected to the shaft 13 by a hub 20 provided With a conical flange 21 upon which radial spokes 22 are mounted. lhe outer ends of these spokes are secured to the inner annular flange lo.

It will be noted that the conical hub flange and the spokes extend at an angle toward the rear annular plate 17 in order to guide the incoming fluid toward the rear portions of the blades.

In the modified form shown in Fig. 5 the inner and outer blades 23 are combined to form one circumferential line in Which onehalf of the blades extend in a direction opposite to the other half. Each inner blade is provided With outer transverse recesses or cuts 24 extending for a distance approximately one-half its Width at a plurality of points, to receive the corresponding inner cut portions of the outer blades Which extend in the opposite direction. rlfhis construction provides a plurality of diamondshaped spaces 25 Which serve to draw in the fluid and discharge it tangentially therefrom in substantially the same manner as in the first form mentioned.

ln order to increase the strength of the` blades Without increasing the thickness of the material, it is desirable, in some cases, to bend a portion 26 of the blade in the manner shown in Fig. 6, the bent portion being formed on the outer edge of the blade.

From the foregoing description it will be seen that the centrifugal fan is so constructed that all parts of the blades share their proportionate load with the result than an eliicient fan is provided.

llhat I claim as my invention is:

1. A centrifugal fan, comprising a rotary drum-like member having numerous elongated blades arranged lengthwise obliquely With relation to the axis of rotation of the member to form comparatively a large intake chamber, approximately one half of the number of blades extending obliquely in4 the opposite direction from the remaining blades, one end of the said member being open to permit unobstructed ingress of the fluid to be moved, and supporting means for said member which Will freely permit the tangential escape of the fluid from the blades of said member.

2. A centrifugal fan, comprising a rotary drum-like member having a plurality of circumferential lines of numerous elongated blades arranged lengthwise obliquely With relation to the axis of rotation of the member to form comparatively a large intake chamber, the blades of one circumferential line extending at an angle With relation to the blades of the adjacent circumferential line, one end of said member being open to permit unobstructed ingress of the fluid to be moved, and supporting means for said member which Will permit the free tangential escape of the fluid from the blades of said member.

3. A centrifugal fan, comprising a rotary drum-like member having a plurality of circumferential lines of numerous elongated blades arranged lengthwise obliquely with relation to the axis of rotation of the member to form comparatively a large intake chamber, the blades of one circumferential line enxtending at an angle With relation to the blades of the adjacent circumferential line and crossing the radial plane of said blades, and supporting means for said member which Will permit the free tangential escape of the fluid from the blades of said member.

4l. A centrifugal fan, comprising a rotary drumlike member having an inner and an outer circumferential line of numerous elongated blades arranged lengthvvise obliquely With relation to the axis of rotation of the said member to form comparatively a large intake chamber, one end of said member being open to permit the ingress of the fluid to be moved, the blades of the inner circumferential line being arranged to direct the one circumferential line extending obliquely L f in the opposite direction to the blades of the other line, one of said plates having a central opening, a hub portion connected to one of the plates, and supporting means for said hub portion which will permit the free tangential escape of the fluid from the blades.

6. A centrifugal fan, comprising a pair of spaced annular plates, an inner and an outer circumferential line of numerous elongated blades extending obliquely from plate to plate and connected thereto the blades of one circumferential line extending obliquely in the opposite direction to the blades of the other line, one of said plates having an inlet opening of a diameter approximately coincident With the diameter formed by the inner edges of the inner circumferential line of blades, a hub portion connected to one of the plates, and a supporting means for said hub portion Which will permit the free tangential escape of the fluid from the blades.

7. A centrifugal fan, comprising a pair of spaced annular plates, an inner and an outer circumferential line of numerous elongated blades extending obliquely from plate to plate and connected thereto, one of said plates having an inlet opening of a diameter approximately coincident with the diameter formed by the inner edges of the inner circumferential line of blades, the blades of 15 ing means for said hub portion Which Will 20 permit the free tangential escape of the iiuid from the blades.

In testimony whereof, I aiix my signature, in presence of two Witnesses.

' ROBERT WARG. Witnesses: v

C. H. KEENEY, EMLLY SCHOWALTER.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

' Washington, D. C. 

